Semiconductor device having a plurality of top surface connection terminals

Abstract

This semiconductor device includes a semiconductor element mounted on a metal layer, first to third connection terminals that are provided on the semiconductor element, a first bus bar bonded to the first connection terminal, and a second bus bar bonded to the second connection terminal. The semiconductor element is bonded to the metal layer, and the first to third connection terminals are disposed on a top surface of the semiconductor element. One end of the first bus bar is bonded to the first connection terminal, another end of the first bus bar is an output unit, one end of the second bus bar is bonded to the second connection terminal, and another end of the second bus bar is bonded to the metal layer. A first surface of the semiconductor element and the second bus bar are at an identical potential.

The invention claimed is: 
     
       1. A semiconductor device comprising:
 a metal layer which is a conductor; 
 a semiconductor element mounted on a first surface of the metal layer; 
 a first connection terminal provided on the semiconductor element; 
 a second connection terminal provided on the semiconductor element; 
 a third connection terminal provided on the semiconductor element; 
 a first bus bar bonded to the first connection terminal, the first bus bar formed as a single conductive member; and 
 a second bus bar bonded to the second connection terminal, 
 wherein a first surface of the semiconductor element is bonded to the first surface of the metal layer, 
 the first connection terminal, the second connection terminal, and the third connection terminal are disposed on a second surface of the semiconductor element, 
 one end of the first bus bar is bonded to the first connection terminal, 
 another end of the first bus bar is an output unit which is exposed to the outside of the semiconductor device, 
 one end of the second bus bar is bonded to the second connection terminal, 
 another end of the second bus bar is bonded to the metal layer, and 
 the first surface of the semiconductor element and the second bus bar are at an identical potential, and 
 a cross-sectional area of the second bus bar in a direction of electrical conduction is larger than a cross-sectional area of the first bus bar in a direction of electrical conduction. 
 
     
     
       2. The semiconductor device according to  claim 1 , further comprising:
 an insulating layer provided on a second surface of the metal layer; and 
 a heat dissipator provided to the insulating layer, 
 wherein a first surface of the insulating layer is in contact with the metal layer, and 
 a second surface of the insulating layer is in contact with the heat dissipator. 
 
     
     
       3. The semiconductor device according to  claim 1 ,
 wherein the semiconductor element is constituted by a gallium nitride-based transistor, 
 the first connection terminal is a drain terminal, 
 the second connection terminal is a source terminal, and 
 the third connection terminal is a gate terminal. 
 
     
     
       4. The semiconductor device according to  claim 1 , wherein the metal layer is a lead frame in which a wiring pattern is formed. 
     
     
       5. The semiconductor device according to  claim 1 , wherein
 the second bus bar includes a plurality of linearly extending conductors and joint section, 
 a first conductor is one of the plurality of linearly extending conductors and extends horizontally with respect to the first surface of the semiconductor element, 
 a second conductor is another one of the plurality of linearly extending conductors and extends vertically with respect to the first surface of the semiconductor element, and 
 the first conductor and the second conductor are connected to each other by the joint section. 
 
     
     
       6. The semiconductor device according to  claim 5 , wherein the first conductor is a rod shape or plate shape. 
     
     
       7. The semiconductor device according to  claim 5 , wherein the second conductor is a rod shape or plate shape.